Scalar fully-heavy tetraquark states $$QQ^\prime {\bar{Q}} \bar{Q^\prime }$$ in QCD sum rules

Very recently, the LHCb Collaboration observed distinct structures with the $$cc{\bar{c}}{\bar{c}}$$ c c c ¯ c ¯ in the $$J/\Psi $$ J / Ψ -pair mass spectrum. In this work, we construct four scalar ($$J^{PC} = 0^{++}$$ J PC = 0 + + ) $$[8_c]_{Q\bar{Q^\prime }}\otimes [8_c]_{Q^\prime {\bar{Q}}}$$ [ 8 c ] Q Q ′ ¯ ⊗ [ 8 c ] Q ′ Q ¯ type currents to investigate the fully-heavy tetraquark state $$Q Q^\prime {\bar{Q}} \bar{Q^\prime }$$ Q Q ′ Q ¯ Q ′ ¯ in the framework of QCD sum rules, where $$Q=c, b$$ Q = c , b and $$Q^\prime = c, b$$ Q ′ = c , b . Our results suggest that the broad structure around 6.2-6.8 GeV can be interpreted as the $$0^{++}$$ 0 + + octet–octet tetraquark states with masses $$6.44\pm 0.11$$ 6.44 ± 0.11 GeV and $$6.52\pm 0.10$$ 6.52 ± 0.10 GeV, and the narrow structure around 6.9 GeV can be interpreted as the $$0^{++}$$ 0 + + octet–octet tetraquark states with masses $$6.87\pm 0.11$$ 6.87 ± 0.11 GeV and $$6.96\pm 0.11$$ 6.96 ± 0.11 GeV, respectively. Extending to the b-quark sector,the masses of their fully-bottom partners are found to be around 18.38-18.59 GeV. Additionally, we also analyze the spectra of the $$[8_c]_{c{\bar{c}}}\otimes [8_c]_{b {\bar{b}}}$$ [ 8 c ] c c ¯ ⊗ [ 8 c ] b b ¯ and $$[8_c]_{c{\bar{b}}}\otimes [8_c]_{b {\bar{c}}}$$ [ 8 c ] c b ¯ ⊗ [ 8 c ] b c ¯ tetraquark states, which lie in the range of 12.51–12.74 GeV and 12.49–12.81 GeV, respectively.

Masses of fully heavy tetraquarks $$QQ {\bar{Q}} {\bar{Q}}$$ in an extended relativized quark model

Inspired by recent measurement of possible fully charmed tetraquarks in LHCb Collaboration, we investigate the mass spectra of fully heavy tetraquarks $$QQ {\bar{Q}} {\bar{Q}}$$ Q Q Q ¯ Q ¯ in an extended relativized quark model. Our estimations indicate that the broad structure around 6.4 GeV should contain one or more ground states for $$cc {\bar{c}} {\bar{c}}$$ c c c ¯ c ¯ tetraquarks, while the narrow structure near 6.9 GeV can be categorized as the first radial excitation of $$cc {\bar{c}} {\bar{c}}$$ c c c ¯ c ¯ system. Moreover, with the wave functions of the tetraquarks and mesons, the strong decays of tetraquarks into heavy quarkonium pair are qualitatively discussed, which can be further checked by the LHCb and CMS Collaborations.

Umowa o pomocy przy zbiorach

The purpose of this article is to define the normative form of a harvesting help contract and to resolve any doubts that may arise in its practical application. Due to the occurrence of accidents in agriculture, it is also necessary to answer the question to what extent the legal regulation of agricultural social insurance should provide protection for farmers’ helpers (assistants) against the loss of their ability to work. In conclusion, the author states that the Insurance Act regulates a new type of contract − a harvesting help contract − but the scope of its regulation raises serious doubts. The legislator has introduced a non-synthetic definition of the term and while only vaguely defining the rights and obligations of the farmer, defines in too much detail those of the helper. The analysed regulation does not provide for any specific form of the contract or its contents regarding the activities of duties performed during harvesting or the level of pay for the work provided. The protection of the helper is limited to the provision of health insurance and accident insurance benefits only. In view of the subject of insurance protection and the specificity of work in agriculture, such a narrow structure, does not seem to be justified.

Various Barbs in Solar Filaments

Interest to lateral details of the solar filament shape named barbs, motivated by their relationship to filament chirality and helicity, showed their different orientation relative to the expected direction of the magnetic field. While the majority of barbs are stretched along the field, some barbs seem to be transversal to it and are referred to as anomalous barbs. We analyse the deformation of helical field lines by a small parasitic polarity using a simple flux rope model with a force-free field. A rather small and distant source of parasitic polarity stretches the bottom parts of the helical lines in its direction creating a lateral extension of dips below the flux-rope axis. They can be considered as normal barbs of the filament. A stronger and closer source of parasitic polarity makes the flux-rope field lines to be convex below its axis and creates narrow and deep dips near its position. As a result, the narrow structure, with thin threads across it, is formed whose axis is nearly perpendicular to the field. The structure resembles an anomalous barb. Hence, the presence of anomalous barbs does not contradict the flux-rope structure of a filament.

Construct Validity of Fluency and Implications for the Factorial Structure of Memory

Fluency is an important construct in clinical assessment and in cognitive taxonomies. In the Cattell–Horn–Carroll (CHC) model, Fluency is represented by several narrow factors that form a subset of the long-term memory encoding and retrieval (Glr) broad factor. The CHC broad classification of Fluency was evaluated in five data sets, and the CHC narrow classification was evaluated in an additional two data sets. The results suggest that Fluency tests are more strongly related to processing speed (Gs) and acquired knowledge (Gc) than to Glr, but Fluency may also be represented as a distinct broad factor. In the two additional data sets with a large number of Fluency tests, the CHC Fluency narrow factors failed to replicate with confirmatory factor analysis. An alternative and simpler narrow structure of Fluency was found, supporting the factorial distinction of semantic versus orthographic Fluency. The results have important implications for the factorial structure of memory, the classification of Fluency tests, and the assessment of Fluency.

Energy Efficiency and QoS Enhancement for Wireless Sensor Networks with Applications to Long-Narrow Structures

There is a class of special environments, such as roads, mines tunnels, rivers, bridges, and pipelines, whose geographical shapes are long-narrow for several hundred meters. Wireless sensor networks (WSN) can be applied to monitor these environments. Long-narrow structure makes the WSN face plenty of challenges, such as unbalanced energy consumption and data aggregation. This paper proposes a nonuniform symmetric cluster model (NUSCM) using reasonable coverage routing controlling. The NUSCM consists of two base stations, sensor node clusters (SNCs) and transmission node clusters (TNCs), which can make the sensor networks be scalable to cover various long-narrow structures. Hierarchical nodes spacing and routing strategy of NUSCM are addressed. Furthermore, we simulate the proposed NUSCM, in comparison with the nonuniform deployment with two base stations (NUD-TBS) and uniform deployment with two base stations (UD-TBS). Research results indicate that the NUSCM and NUD-TBS have the same energy efficiency, which are better than that of UD-TBS. Moreover, NUSCM is superior to the UD-TBS and NUD-TBS in the link communication load and network survivability.